The graph of the equation y=ax2+bx+c, where a, b, and c are constants, is a parabola with an axis of symmetry as x=−3. Find ba .
axis of symmetry at x=−3⇒a(x+3)2+c=ax2+6ax+(9+c)ba=6aa=6
The cheater way to do it is to remember that the axis of symmetry is at
x=−b2aso here−3=−b2aba=(−3)(−2)=6
+537 
